1. Field of the Invention
The present invention relates to a robot having a line distribution board to which a plurality of lines connected to an outer apparatus are attached.
2. Description of the Related Art
An industrial robot is provided at its wrist portion with detachable outer apparatus, such as a welding gun and a hand for holding a workpiece, depending on its application. A plurality of lines, which are necessary according to the type of an end effector, for example, cables for supplying power or sending signals, or tubes for supplying cooling water or air used for driving, are arranged in the robot. In many cases, these lines are attached to a single line distribution board through connectors attached to end portions of the lines.
Japanese Patent JP-B-4349320 discloses a technique for facilitating a replacing process of a supplying unit and a wiring process, which is necessary for the replacing process, by selectively connecting an inner cable connected to the supplying unit for supplying power, air or gas, and an outer cable connected to outer apparatus with each other.
According to the configuration in which lines are attached to a single line distribution board, in the case where it is necessary to replace a line due to changes in usage or the like, the line distribution board itself has to be replaced. Therefore, even though some of the cables are not required to be replaced, all of the cables have to then be detached from the line distribution board. After completion of the replacing process, these cables are attached again to the line distribution board. Accordingly, due to the cable detaching process and the cable attaching process, which are not essential, the time necessary for the cable replacing process is increased and the cost is also increased.
According to Japanese Patent JP-B-4349320, a connector must be attached to each line beforehand, which results in increased cost. In addition, as the application of the robot is diversified, various types of outer apparatus are used with the robot, and cables used for such outer apparatus are manufactured according to various standards. Accordingly, in order to make it possible to use for various applications without replacing the lines such as cables, it is necessary to provide lines with great versatility. However, such lines are expensive, which results in increased cost.
Accordingly, there is a need for an industrial robot which facilitates replacement of lines, depending on the application.